3-phosphoranylidene ethyl cephalosporins

ABSTRACT

A new group of cephalosporin compounds characterized by possessing as 3-position substituent a phosphoranylidene ethyl group. The new compounds can be used as intermediates in the production of cephalosporin antibiotics characterized by possessing an ethyl or substituted ethyl group as 3-position substituent.

United States Patent [191 Weir [ 3-PHOSPHORANYLIDENE ETHYL ICEPHALOSPORINS [75] Inventor: Niall Galbraith Weir, London,

England [73] Assignee: Glaxo Laboratories Limited,

Greenford, Middlesex, England 22 Filed: July 30,1971

21 Appl.No.: 167,870

[ 30] Foreign Application Priority Data Aug. 6, 1970 Great Britain38020/70 [52] US. Cl. 260/243 C, 424/246, 260/2391, 424/271 [51] Int.Cl. C071! 99/24, C07d 99/16 [58] Field of Search 260/243 C Dec. 10, 1974[56] References Cited UNITED STATES PATENTS 3,173,916 3/1965 Shull eta1..... 260/243 C Primary Examiner-Nicholas S. Rizzo Attorney, Agent, orFirmBacon & Thomas 5 7 ABSTRACT 6 Claims, No Drawings3-PHOSPHORANYLIDENE ETHYL CEPHALOSPORINS This invention is concernedwith improvements in or relating to cephalosporin compounds.

The cephalosporin compounds referred to in this specification aregenerally named with reference to cepham (see J. Amer. Chem. Soc. 1962,84, 3400). The term cephem refers to the basic cepham structure with onedouble bond. Where a dotted line bridges the 2-, 3- and 4-positions thisindicates that the compound may be a ceph-2-em or a ceph-3-em compound.

My invention is concerned with a novel group of cephalosporin compoundsthat are of value as intermediates in the production of cephalosporincompounds possessing antibacterial activity. As is well known in the artA -4-carboxy cephalosporin antibiotics are compounds which are generallydepicted by the formula 1 5 R NH (wherein R is a carboxylic acyl groupand R is the 3- position substituent). My new intermediates are of valuein that they can be used to produce a variety of cephalosporinantibiotics characterized by possessing an ethyl or substituted ethylgroup as 3-position substituent.

My new cephalosporin compounds possess a phosphoranylidene ethyl groupat the 3-position and may be prepared by reacting a corresponding3-halomethyl compound with a particular class of carbanions derived fromphosphorus ylids.

The phosphoranylidene ethyl group may be depicte as follows wherein R isan organic group or a hydrogen atom and the R groups, which may be thesame or different, are each organic groups. In subsequenttransformations the moiety P(R will generally bedisplaced so that thenature of the group R is not critical.

Compounds containing the phosphoranylidene group may be reacted with anacid HX to form compounds possessing the group 3 7 ca ca P(R3)S-fluorophenylthioacetyl,

(wherein R is a carboxylic acyl group, R is hydrogen or acarboxyl-blocking group, Z is S or S 0 and R and R have the abovedefined meanings).

The group R in the above formula may represent a wide variety of acylgroups which may contain 1-20 carbon atoms. Specific acyl groups areillustrated in the accompanying list which is not intended to beexhaustlve:

i. R"C,,H ,,CO where R" is aryl (carbocyclic or het-' erocyclic), orcycloalkyl, substituted aryl, substituted cycloalkyl, cyclohexadienyl,or a non-aromatic heterocyclic or mesoionic group, and n is an integerfrom 14. Examples of this group include phenylacetyl; substitutedphenylacetyl e.g. fluorophenylacetyl, nitrophenylacetyl,aminophenylacetyl, acetoxyphenylacetyl, methoxyphenylacetyl,methylphenylacetyl, or

hydroxyphenylacetyl; ,N,N-bis (2-chloroethyl) aminophenylpropionyl;thien-2- and 3-ylacetyl; 4-isoxazolyl and substituted4-isoxazolylacetyl; pyridylacetyl; tetrazolylacetyl or a sydnoneacetylgroup. The substituted 4-isoxazolyl group may be a 3-aryl-5-methylisoxazol- 4-yl group, the aryl group being e.g. phenyl or halophenyle.g. chloroor bromophenyl. An acyl group of this type is3-o-chlorophenyl-5-methylisoxazol-4-ylacetyl.

ii. C H CO where n is an integer from 1-7. The alkyl group may bestraight or branched and, if desired, may be interrupted by an oxygen orsulphur atom or substituted by e.g. a cyano group, a carboxy group, analkoxycarbonyl group, a hydroxy group or a carboxycarbonyl group(CO.COOH). Examples of such groups include cyanoacetyl, hexanoyl,heptanoyl, octanoyl and butylthioacetyl. I

iii. C H CO where n is an integer from 2-7. The alkenyl group may bestraight or branched and, if desired, may be interrupted by an oxygen ora sulphur atom. An example of such a group is allylthioacetyl.

R 0C-C0- where R has the meaning defined under (i) and in addition maybe benzyl, and R" and R' which may be the same or different eachrepresent hydrogen, phenyl, benzyl, phenethyl or lower alkyl. Examplesof such groups include phenoxyacetyl, 2-phenoxy-2- phenylacetyl,benzyloxyacetyl, ,2-phenoxypropionyl, 2-phenoxybutyryl,methylthiophenoxyacetyl.

where R has the meaning defined under (i), and, in addition, may bebenzyl and R and R' have the meanings defined under (iv). Examples ofsuch groups include S-phenylthioacetyl, S-chlorophenylthioacetyl,pyridylthioacetyl, and S-benzylthioacetyl.

vi. RZ(CH ),,,CO- where R has the meaning defined under (i) and, inaddition, may be benzyl, Z is an oxygen or sulfur atom and m is aninteger from 25. An example of such a group is S-benzylthiopropionyl.

vii. RCO- Where R has the meaning defined under (i). Examples of suchgroups include benzoyl, substituted benzoyl (e.g. aminobenzyl),4-isoxazolyland substituted 4-isoxazolylcarbonyl, cyclopentanecarbonyl,sydnonecarbonyl, naphthoyl and substituted naphthoyl (e.g.2-ethoxynaphthoyl), quinoxalinylcarbonyl and substitutedquinoxalinylcarbonyl (e.g. 3-carboxy- Z-quinoxalinylcarbonyl). Otherpossible substituents for benzoyl include alkyl, alkoxy, phenyl, phenylsubstituted by carboxy, alkylamido, cycloalkylamido, allylamido,phenyl(lower)alkylamido, morpholinocarbonyl, pyrrolidinocarbonyl,piperidinocarbonyl, tetrahydropyridino, furfurylamido orN-alkyl-N-anilino, or derivatives thereof, and such substituents may bein the 2 or 2- and 6- positions. Examples of such substituted benzoylgroups are 2,6-dimethoxybenzoyl, 2- methylamidobenzoyl and2-carboxybenzoyl. Where the group R represents a substituted4-isoxazolyl group, the substituents may be as set out above under (i).Examples of such 4-isoxazolyl groups are 3'phenyl-5- methylisoxazol-4-ylcarbonyl, 3-o-chlorophenol-5- methyl-isoxazol-4-yl carbonyl and 3-( 2,6- dichlorophenyl)-5-methyl-isoxazol-4-yl carbonyl.

(viii) ta -ome where R has the meaning defined under (i) and X is amino,substituted amino (e.g. acylamido or a group obtained by reacting thea-aminoacylamido group of the 7-side chain with an aldehyde or ketone,e.g. acetone, methylethylketone or ethyl acetoacetate), hydroxy,carboxy, esterified carboxy, azido, triazolyl, tetrazolyl, cyano,halogeno, acyloxy (e.g. formyloxy or lower alkanoyloxy) or etherifiedhydroxy group. Examples of such acyl groups are a-aminophenylaceyl, anda-carboxyphenylacetyl.

R -C-CO- where R, R" and R which may be the same or different may eachrepresent lower alkyl, phenyl or substituted phenyl or R representshydrogen. An example of such an acyl group is triphenylmethylcarbonyl.

x. R"-Nl-I-CO- where R has the meaning defined under (i) and in additionmay be hydrogen, lower alkyl or halogen substituted lower alkyl. Anexample of such a group is CI(CH NHCO.

where X has the meaning defined under (viii) above and n is an integerof from 1 to 4. An exampie of such an acyl group isl-aminocyclohexanecarbonyl.

xii. Amino acyl, for example R CH(Nl-l )-(CH ),,CO where n is an integerfrom l-lO, or NH C,,H ,,Ar(Cl'l CO, where m is zero or an integer from1-10, and n is O, I or 2, R is a hydro gen atom or an alkyl, aralkyl orcarboxy group or a group as defined under R above, and Ar is an arylenegroup, e.g. p-phenylene or l,4-naphthylene. Examples of such groups aredisclosed in British Pat. specification No. 1,054,806. A group of thistype is the paminophenylacetyl group. Other acyl groups of this typeinclude those, e.g. S-aminoadipoyl, derived from naturally occurringamino acids, and derivatives thereof e.g. N-benzoyl-S-aminoadipoyl.

xiii. Substituted glyoxylyl groups of the formula R CO-CO- where R is analiphatic, araliphatic or aromatic group, e.g. a thienyl group, a phenylgroup, or a mono-, dior trisubstituted phenyl group, the substituentsbeing, for example, one or more halogen atoms (F, Cl, Br, or I), methoxygroups, methyl groups or amino groups, or a fused benzene ring. Includedin this group are also the a-carbonyl derivatives of the abovesubstituted glyoxylyl groups.

xiv. Forrnyl.

If it is intended to effect a subsequent reaction on the compound offormula I two important species of R groups are:

xv. l-lydrocarbyloxycarbonyl and substituted hydrocarbyloxycarbonylgroups (wherein the 7-amino group forms part of a urethane), e.g. loweralkoxycarbonyl groups (such as methoxycarbonyl), ethoxycarbonyl andt-butoxycarbonyl groups); halo lower alkoxycarbonyl groups e. g.2,2,2-trichloroethoxycarbonyl; aralkoxycarbonyl groups such asbenzyloxycarbonyl, 4-methoxybenzyloxycarbonyl, diphenylmethoxycarbonyland 4-nitrobenzyloxycarbonyl groups; and cycloalkoxycarbonyl groups e.g.adamantyloxycarbonyl.

xvi. Haloformyl e.g. chloroformyl.

The invention also comprises a process for the preparation of thecompounds of formula I which comprises reacting a 3-halo-(i.e. bromo-,iodoor chloro) methyl cephalosporin compound with a phosphorus ylid offormula III below. This aspect of the invention will now be described ingreater detail with reference to the cephalosporin starting materials,the phosphorus ylid, the reaction conditions and subsequenttransformations.

CEPHALOSPORIN STARTING MATERIALS The 3-halomethyl cephalosporincompounds used as starting materials may be defined as having thegeneral formula 2 R NH I N O II Cl-l l compounds can be prepared fromthe corresponding chlorides and bromides e.g. by reaction with an alkalimetal iodide.

Ceph-3-em compounds of formula (II) can also be prepared by halogenationof a 3-methyl cephalosporin sulphoxide as described in Belgian Pat. No.755,256.

Ceph-Z-em compounds of formula (II) may also be prepared by the methodof Dutch published Pat. application Ser. No. 6902013 by reaction of aceph-2-em-3- methyl compound with N-bromosuccinimide to yield theceph-2-em-3-bromomethyl compound.

Compounds containing a sulphur atom at the 1- position of the cephemnucleus may be oxidised to the corresponding sulphoxides by methodsanalogous to those described by Chow, Hall and Hoover (J. Org. Chem.1962, 27, 1381). The cephalosporin compound is mixed with the oxidisingagent in an amount such that at least one atom of active oxygen ispresent per atom of thiazolidine sulphur. Suitable oxidising agentsinclude metaperiodic acid, peracetic acid, permonophthalic acid,iodobenzene dichloride, mchloroperbenzoic acid or t-butyl hypochlorite,the latter being preferably used in admixture with a weak base e.g.pyridine. The l-oxide may be obtained in the aand/or B-form.

The group protecting the 4-carboxyl group may be formed with an alcohol(aliphatic or araliphatic), phenol, silanol, stannanol or acid which mayreadily be split off at a later stage of the reaction.

Suitable esters thus include compounds containing as 4-ester group, agroup selected from the following list which is not intended to be anexhaustive list of possible ester groups i. ---COOCR RR wherein at leastone of R, R and R" is an election-donor e.g. p-methoxyphenyl,2,4,6-trimethylphenyl, 9-anthryl, methoxy, acetoxy or fur-2-yl. Theremaining R- R" and R groups may be hydrogen or organic substitutinggroups. Suitable ester groups of this type includep-methoxybenzyloxycarbonyl and 2,4,6- trimethylbenzyloxycarbonyl.

COOCRRR wherein at least one of R, R and R is an electron-attractinggroup e.g. benzoyl, pnitrophenyl, 4-pyridyl, trichloromethyl,tribromomethyl, iodomethyl, cyanomethyl, ethoxycarbonylmethyl,arylsulphonylmethyl, 2-dimethylsulphoniumethyl, o-nitrophenyl or cyano.The remaining R, R" and R groups may be hydrogen or organic substitutinggroups. Suitable esters of this type include benzoylmethoxycarbonyl,p-nitrobenzyloxycarbonyl, 4-pyridylmethoxycarbonyl,2,2,2-trichloroethoxycarbonyl and 2,2,Z-tribromoethoxycarbonyl.

iii. COOCRRR wherein at least two of R, R and R are hydrocarbon such asalkyl e.g. methyl or ethyl, or aryl e.g. phenyl and the remaining R, R"and R group, if there is one, is hydrogen. Suitable esters of this typeinclude, t-butyloxycarbonyl, t-amyloxycarbonyl, diphenylmethoxycarbonyland triphenylmethoxycarbonyl.

iv. -COOR" wherein R is adarnantyl, 2- benzyloxyphenyl,4-methylthiophenyl, tetrahydropyran-2-yl or tetrahydrofur-Z-yl.

Silyl esters may conveniently be prepared from a halosilane or asilazane of the formula R SiX; R zsixz; R 3Si'NR 2; R 3Si'NH' COR; RSi-NH'CO-NH-SiR R NH'CO'NR 'SiR or R C(OSiR NSiR where X is a halogenand the various groups R, which can be the same or different, representhydrogen atoms or alkyl, e.g. methyl, ethyl, npropyl, iso-propyl; aryl,e.g. phenyl; or aralkyl e.g. benzyl groups.

Preferred derivatives of silanols are silyl chlorides such as forexample trimethylchlorosilane and dimethyldichlorosilane.

The carboxyl groups may be regenerated from an ester by any of the usualmethods; for example, acidand base-catalysed hydrolysis (especially forsilyl and stannyl esters) is generally applicable, as well asenzymically-catalysed hydrolyses; however, aqueous mixtures may be poorsolvents for these compounds and they may cause isomerizations,rearrangements, side-reactions, and general destruction, so that specialmethods may be desirable. Five suitable methods of deesterification are:

i. Reactions with Lewis acids: Suitable Lewis acids for reaction withthe esters include trifluoroacetic acid, formic acid, hydrochloric acidin acetic acid, zinc bromide in benzene and aqueous solutions orsuspensions of. mercuric compounds. The reaction with the Lewis acid maybe improved by addition of a nucleophile such as anisole.

ii. Reduction: Suitable systems for effecting reduction are zinc/aceticacid, zinc/formic acid, zinc/- lower alcohol, zinc/pyridine,palladised-charcoal and hydrogen, electrolysis, and sodium and liquidammonia.

iii. Attack by nucleophiles: Suitable nucleophiles are those containinga nucleophilic oxygen or sulphur atom for example alcohols, mercaptans,thiocyamates and water.

iv. Oxidative methods: for example, those which involve the use ofhydrogen peroxide and acetic acid.

v. Irradiation.

PHOSPHORUS YLID Phosphorus ylids which may be used in the processaccording to the invention include those having the general formula (RP=CH-R lll. wherein R and R have the above defined meanings.

When employing ceph-3-em compounds as the sulphides we prefer that thephosphorus ylid is chosen from those having a pKa (in water: ethanol 8:2v/v) of from 6.5 to 12 at 25 to facilitate the desired reaction.

The nature of R will depend on the nature of the compound to be producedand the reaction conditions involved. When employing ceph-3-em compoundsR should be an electronegative groups. Suitable electronegative groupsinclude ester groups, acyl groups, nitro groups and nitrile groups. Thusthe electronegative group may be -CO R COR, -CON(R) S- (O)R -S(O) R NOor CN wherein R may represent an alkyl group, e.g. a lower alkyl groupsuch as methyl, ethyl, n-propyl or isopropyl; an aralkyl group such asbenzyl; an aryl group such as phenyl or naphthyl; or a cycloalkyl groupsuch as cyclohexyl or cyclopentyl, and R is a hydrogen atom or any ofthe R groups.

When employing ceph-2-em compounds, the nature of R is not so critical:it may or may not be electronegative and may be selected from hydrogen,lower alkyl,

propylene oxide) which may be generated with halide ion, and fluorideion in an aprotic solvent.

The reactant ylid (III) must be used in an amount of at least one molarproportion either in association with a base stronger than the conjugatebase of the phosphonium compound or in association with a further molarproportion of the ylid (III) which itself may function as the desiredbase.

The use of a base at this stage in conjunction with a ceph-2-em compoundmay convert the cephalosporin compound to a ceph-3-em compound. Thisenables a convenient isomerisation to be simultaneously effected.

REACTION CONDITIONS The reaction may be carried out by stirring thecomponents together, e.g. at a temperature of from 80 to +80C,preferably from l to +C. When the reaction is effected at a temperatureat which one or more reactants may volatilse a closed system may beused. The reaction may be effected in an inert or relatively inertsolvent, for example, a halogenated hydrocarbon, e.g. methylenechloride; a hydrocarbon eg benzene; an acrylic or cyclic ether e.g.diethyl ether, tetrahydrofuran or dioxan; dimethylsulphoxide; an amidee.g. dimethylformamide or dimethylacetamide; an ester e. g. a loweralkyl alkanoate such as ethyl acetate, or hexamethylphosphoramide. Thecourse of the reaction may also be followed by thin-layer or paperchromatography, by electrophoresis and by spectroscopy.

Although we do not wish to be bound by theoretical considerations it isbelieved that the reaction of the 3- halomethyl cephalosporin compoundof formula (II) with the phosphorus ylid of formula (III) to form acompound of formula (I) proceeds as follows:

CH-R

COOR

SUBSEQUENT TRANSFORMATIONS N cn cs a COOl-l (wherein R is a carboxylicacyl group which may be the group R, and R and R have the above-definedmeanings) and non-toxic derivatives thereof may be prepared from acompound of formula (I) by (A) cleavage of the carbon-phosphorus bond.Any of the following reactions (B) may be carried out before or aftersaid cleavage (i) conversion of a A -isomer into the desired A -isomer(ii) removal of any groups protecting any carboxyl groups (iii)reduction of a compound in which Z is S 0 to form the desired 2 Scompound and (iv) deacylation of a compound in which R does not equal Rto form a 7-amino compound followed by reacylation to introduce thedesired 7-RNH- group.

Cleavage of the carbon-phosphorus bond may be achieved by, for example,reduction or by hydrolysis. Reduction may be effected with the aid ofaluminum amalgam, palladised charocal/hydrogen or zinc/l-lCl.

Compounds of formula (V) wherein R is an alkoxycarbonyl group are novelcompounds useful as cephalosporin antibiotics. The invention thusincludes within its scope compounds of the general formula R NH ! 8 O CHCH CO,OR (VI) COOH wherein R has the above-defined meaning andR is loweralkyl.

Compounds of general formula (VI) and non-toxic derivatives thereof,e.g. base salts (where applicable) and acid addition salts (whereapplicable), possess antibacterial activity against a range of organismsand are of value in human and veterinary medicine. They may also be ofvalue in the preparation of other 3- substituted cephalosporincompounds. By the term non-toxic as applied to the compounds of formula(VI) we mean those derivatives which are physiologically acceptable inthe dosage at which they are administered.

Salts which may be formed from the compounds according to the inventioninclude (a) inorganic base salts such as alkali metal e.g. sodium andpotassium, alkaline earth e.g. calcium, and organic base salts e.g.procaine and dibenzylethylene diarnine salts and (b) acid addition saltsof any possible basic functions e.g. amino e.g. with hydrochloric,hydrobromic, sulphuric, nitric, phosphoric, toluene-p-sulphonic andmethanesulphonic acids. The salts may also be in the form of resinates,formed, e.g. with a polystyrene resin containing amino, quaternaryamino, or sulphonic acid groups, or a resin containing carboxyl groups,e.g. a polyacylic acid resin. The resin may if desired be cross-linked,e.g. it may be a copolymer of styrene and divinylbenzene containing theappropriate groups.

There will now be discussed subsequent reactions (B) that may beeffected before, but preferably after, the cleavage reaction discussedabove.

Where the resultant compound contains a sulphinyl group at thel-position this may be reduced by any convenient means. This may, forexample, be effected by reduction of the corresponding acyloxysulphoniumor alkyloxysulphonium salt prepared in situ by reaction with e.g. acetylchloride in the case of an acetoxysulphonium salt, reduction beingeffected by, for example, sodium dithionite or by iodide ion as in asolution of potassium iodide in a water miscible solvent e.g. aceticacid, tetrahydrofuran, dioxan, dimethylformamide or dimethylacetamide.The reaction may be effected at a temperature of to +50C.

Alternatively, reduction of the l-sulphinyl group may be effected byphosphorus trichloride or tribromide in solvents such as methylenechloride, dimethylformamide or tetrahydrofuran, preferably at atemperature of 20C to +50C.

An advantage associated with the use of a sulphoxide is that thecompound will generally be a [k -compound.

Where the resultant compound is a ceph-2-em compound, the desiredceph-3-em compound may be obtained by treatment of the former with abase.

Removal of any groups protecting any amino or carboxyl groups may beeffected as described above.

Where the final product of the above reactions is a 7,8-acylamidocompound not having the desired acyl group, the 7B-acylamido compoundmay be N- deacylated to yield the corresponding 7B-amino compound andthe latter acylated with an appropriate acylating reagent.

Suitable methods of N-deacylating cephalosporin derivatives having7B-acylamido groups are described in British Pat. Nos. 1,041,985 and 1,119,806; Belgian Pat. No. 719,712 and in South African Pat. specificationNos. 68/5048 and 68/5327. Another method of N- deacylation which may beused is acid catalysis. For example, N-deformylation of a 7B-formamidogroup may be effected with a mineral acid at a temperature of minus 15to 100C, preferably +15 to 40C. N- deformylation may be effected withthe aid of a Lewis acid in a lower alkanol, preferably undersubstantially anhydrous conditions.

The compounds of formula (VI) may be formulated for administration inany convenient way, by analogy with other antibiotics and the inventiontherefore includes within its scope a pharmaceutical compositioncomprising a compound of formula (VI) or a non-toxic derivative e. g.salt thereof (as herein defined) adapted for use in human or veterinarymedicine. Such compositions may be presented for use in conventionalmanner with the aid of any necessary pharmaceutical carriers orexcipients. The compoditions may contain from 0.1% upwards, preferablyfrom 10-60% of the active material, depending on the method ofadministration. Where the compositions comprise dosage units, each unitwill preferably contain 500 mg. of the active ingredient. The dosage asemployed for adult human treatment will preferably range from 100-8,000mg. for instance 1,500 mg. per day, depending on the route and frequencyof administration.

Compounds of formula (VI) according to the invention may be administeredin combination with other therapeutic agents such as antibiotics, forexample other cephalosporins, the penicillins or tetracyclines.

The following examples illustrate the invention. In the examples:

System B is n-butanol:ethanol:water 4:1:5, equilibrated at roomtemperature, the upper phase being used as developer in descendingmanner, in equilibrium with lower phase, on Whatman No 1 paper bufferedto pH 6 with 0.05M sodium dihydrogen phosphate.

System C is ethyl acetate: n-butanol: 0.1M-sodium acetate pH 5 8:1:8,equilibrated at 38C, the upper phase being used as developer indescending manner, in equilibrium with lower phase at 38,on No. 1Whatman paper buffered to pH 5 with 0.1M sodium acetate.

Light petroleum was the fraction, b.p. 40 to Methylene chloride wasdried on Woelm Grade I basic alumina. Thin-layer chromatography wascarried out upwards on Merck silica plates.

Nmr spectra were measured at 60 and Mhz. Signs of the coupling constantscannot be attributed.

As far as possible, analytical values for solvates were confirmed byinspection for the appropriate features in the spectra.

The conditions for electrophoresis are those described by Cocker et al.,J. Chem. Soc. 1965, 5015.

Organic solutions were dried over desiccated magnesium sulphate.

EXAMPLE 1 3-( Z-Ethoxycarbonylethyl )-7B-( 2-thienylacetamido)ceph-3-em-4-carboxylic Acid The title compound wasprepared via the following reaction scheme. The steps are described inmore detail below. t-Butyl 3-hydroxymethyl-7B-(2-thienylacetamido)ceph-3-em-4-carboxy1ate t-Butyl 3-ch1oromethy1-7B-(Z-thienylacetamido )ceph- 3-em-4-carboxy1ate t-Butyl3-iodomethy1-7B-(2-thienylacetamido)ceph-3- em-4-carboxy1ate t-Butyl 3-(2-ethoxycarbonyl-2- triphenylphosphoranylideneethyl )-7B-( 2-thienylacetamido)ceph-3-em4-carboxylate Y 3-( 2-ethoxycarbony1ethyl)-7B-( 2- thienylacetamido )ceph-3-em-4-carboxy1ate 32-Ethoxycarbonylethyl )-7B-( 2- thienylacetamido )ceph-3-em-4-carboxylicacid t-Butyl 3-Ch1oromethyl-7B-( 2-thienylacetamido)ceph-3-em-4-carboxy1ate A. solution of t-butyl 3-hydroxymethyl-7B-(2-thienylacetamido)ceph-3-em-4-carboxylate (24 g. prepared as described inExample 6 of Belgian Pat. No. 755,505) in dry peroxide-freetetrahydrofuran (180 ml.) with pyridine (18 ml., 4 equiv.) was run intoa vigorously stirred mixture of thionyl chloride (8.4 m1., 2 equiv.) intetrahydrofuran (1 10 ml.) at ca over 40 minutes. The mixture wasstirred for a further minutes then poured into N-hydrochloric acid(1,000 m1.) and the total extracted with ethyl acetate. The extractswere washed with water and aqueous sodium bicarbonate, then with furtheramounts of water, and dried and evaporated in vacuo. The residue waswashed with ether to give the chloromethyl compound (18.4 g.) as acrystalline solid. This material was recrystallised from acetone(containing some ether) petroleum to give the pure chloromethyl compound(17 g.) as prisms, m.p. with darkening 135, [oz] 4.2 (c 1.9, CHC1 A(EtOH) 266 nm. (5, 7,900), u (CHBr 3460 (NH), 1790 (B-lactam), 1722 (COR) and 1690 and 1514 cm (CONH), 'r (CDCl 3.32 (NH, doublet, J 9 Hz),4.20 (C ,,H, double doublet, l9 and 4.5 Hz), 5.07 (G -H, doublet, J 4.5Hz), 5.47 and 5.61 (Cl-1 C], AB-quartet, J 12 Hz), 6.20 (CH CONH), 6.36and 6.62 (C -CH AB-quartet, J 18 Hz), and 8.50 (C[CH (Found C, 50.2; H,4.85; CI, 7.8; N, 6.3; S, 14.8. C, 1-1 C1N O S requires C, 50.4; H, 4.9;Cl 8.3; N, 6.5; S, 14.95%).

b. t-Butyl 3-iodomethyl-7B-(2-thienylacetamido)ceph- 3-em-4-carboxylateA solution of t-butyl 3-chloromethyl-7B-(2-thienylacetamido)ceph-3-em-4-carboxylate (8.58 g) in acetone (50 ml.)was treated with a solution of sodium iodide (9 g.) in acetone (50 ml.)and the mixture stirred in the dark at 20 for 2% hours. The mixture waspoured into saturated brine and extracted with ethyl acetate. Theextract was washed quickly with 10% aqueous sodium thiosulphate andwater, dried and evaporated in vacuo. The residue was washed with etherto give the iodomethyl compound (6.86 g.) as pale yellow prisms, m.p.123-127 (decomp), [01],, 60 (c, 1.0 CHCl )t,,,,,,, (EtOl-l) 288 nm. (57,750), 11 (CHBr 3478 (NH), 1791 (,B-lactam), 1722 (C0 11) and 1690 and1516 (CONH), 1(CDCl 304 (NH, doublet J 9 Hz), 4.27 (C -,,H, doubledoublet, J 9 and 4.5 Hz), 5.07 (C -14, doublet, J 4.5 Hz) 5.66 (CH I,singlet), 6.17 (CH CONH), 6.6 and 6.27 (C -CH AB-quartet, J 18 Hz), and8.46 (C[Cl-l (Found: C, 42.2; H, 4.2 H, 5.5;"S, 12.6. c a m os requires:C, 41.5; H, 4.05; N, 5.4; S, 12.3%).

c. t-Butyl 3-(2-Ethoxycarbonyl-2- triphenylphosphoranylideneethyl )-7B-(2- thienylacetamido)ceph-3-em-4-carboxylate A solution of t-butyl3-,iodomethyl-7B-(2- thienylacetamido)ceph-3-em-4-carboxylate (3.65 g.,7 mmole) in ethyl acetate (40 ml.) was treated with a solution ofethoxycarbonylmethylenetriphenylphosphorane (4.9 g., 14 mmole) in ethylacetate (50 ml) and the mixture stirred at 3 for 18 hours. Materialwhich had crystallised out after this period was isolated by filtrationand dissolved in methylene dichloride (ca 50 ml.). The organic solutionwas washed with N- hydrochloric acid (3 X ca 50 ml), water (3 X ca 50ml), half saturated aqueous sodium bicarbonate solution (2 X ca 50 m1.)and finally water (2 X ca 50 m1.), and dried and evaporated in vacuo.The residual foam was crystallised from ethyl acetate to give the titlecompound (3.35 g., 64.5%) as photosensitive prisms mp. (darkening at168) 174 (decomp). [01],, +60 (c 1.5, CHCl )t (EtOH) 266 nm. (e, 9,920)and 272 nm. (6, 9.470) 11 (CHBr 3390 (NH), 1780 (B-lactam), 1710 (CO-R), 1680 and 1518 (CONH), and 1605 cm (P#ICO Et), p.m.r. spectrum showedca 6 mole ethyl acetate which masked some of the CO Et bands. A sample(280 mg.) was recrystallised from acetone to give the phosphorane (200mg.) as photosensitive white prisms, mp. (darkening at 168) 176 decomp.[a] +64.3 (c 1.4 CHCl A (EtOH) 266 nm. (6, 10,200) and 272.2 nm (a,9.700), 11 (nujol) 3230 and 3195 (NH), 1775 (B-lactam), 1712 (CO R),1582 and 1590 (P=CCO Et; corresponding to two rotational isomers), 1675and 1542 (CONH) and 1438 cm (P Ph u (CHBr 3390 (NH), 1780 (B-lactam),1710 (C0 12), 1680 and 1518 (COHN), 1605 (P=CCO Et) and 1445 cm- (P Ph r(CDC1 3.4 (NH doublet, J 9 Hz), 4.44 (C -H double doublet, J 9 and 4.5Hz), 5.3 (C H, doublet, J 4.5 Hz), ca 6.0 (OCH CH complex) 6.22 (CHCONH), 6.1 to 6.7 (C -CH and CH C=P complex), 7.87 (acetone ca 16 mole),8.65 (C[CH 8.84 and 9.55 (OCH CH two triplets in ratio 1:2 [total 3protons] corresponding to rotational isomers [see H. 1. Zeliger. J. P.Synder and H. J. Bestmann, Tetrahedran Letters 1969, 2199]). (Found: C,65.2; H, 5.65; N, 3.55; P, 4.3; S, C40H41N2O6PS2.1/3 requires C, H, 5.7;N, 3.7; P, 4.1; S, 8.45%).

d. t-Butyl 3-( Z-Ethoxycarbonylethyl )-7B-( 2thienylacetamido)ceph-3-em-4-carboxylate A solution of t-butyl3-(2-ethoxycarbonyl-2- triphenylphosphoranylideneethyl)-7B-( 2-thienylacetamido)ceph-3-em-4-carboxylate (500 mg.) in tetrahydrofuranml.) was treated with aluminum amalgam(500 mg., prepared as described inL. G. Fieser and M. Fieser, Reagents for Organic Synthesis, p. and water(0.2 ml), and the mixture stirred at 23. After 2 and 3 hours furtheramounts (0.2 ml., and 0.1 ml. respectively) of water were added. After atotal of 4 hours the mixture was filtered and the filtrate evaporated invacuo. The residue was dissolved in benzene. and filtered through ashort column of Merck Kieselgel (0.05 0.2mm, 10 g.) to give, onevaporation, triphenylphosphine (130 mg., 73%). Further elution withbenzene ethyl acetate (1:1) gave the title compound (230 mg., 72%) as afoam, 11 (EtOH) 270 nm (5, 5,020), v,,,,,,, (CHBr 3450 and 3360 (NH),1786 (B-lactam), 1730 (CO R) and 1686 and 1518 cm (CONH), 'r (CDCl 3.51(NH, doublet, J 9 Hz), 4.26 (C -H, double doublet, J 9 and 4.5 Hz), 5.09(G -H, doublet, J 4.5 Hz), 5.88 and 8.74 (OCH CH quartet and triplet),6.17 (CH CONH), 6.50 and 6.8 (C -CH AB-quartet, J 18 Hz), 7.3 7.7 (-CHCH --O-, 4 proton multiplet) and 8.47 (C[CH e.3-(Z-Ethoxycarbonylethyl)-7B-(2- thienylacetamido)ceph-3-em-4-carboxylicAcid t-Butyl 3-(2-ethoxycarbonylethyl)-7B-(2-thienylacetamido)ceph-3-em-4-carboxylate (500 mg.) with anisole (0.5ml.) was treated with trifluoroacetic acid (2 ml. After ca 5 minutes at23 the solvents were removed in vacuo. The residue was partitioned between ethyl acetate and dilute aqueous sodium bicarbonate solution. Thealkaline solution was extracted thoroughly with further amounts of ethylacetate, then taken to pH 2 with N-hydrochloric acid. The mixture wasextracted with ethyl acetate and the extracts washed with water, thendried and evaporated in vacuo. The residue was dissolved in ethylacetate and the solution run into vigorously stirred petroleum ether(b.p. 40 to 60) to give the acid (215 mg.) as an amorphous solid, mp. ca65, [01],, 73 (C 1.0, 2% NaH- CO 11 (0.1 M pH 6 phosphate buffer) 259.5nm. (6 6,280), v (Nujol) ca 3,500 (H 0), 3320 (NH), ca 2600 and 1700 (COH), 1780 (B-lactam), 1730 (CO R) and 1670 and 1540 cm (CONH), 1' (D 0,with NaHCO 2.68 and 2.96 (thienyl), 4.41 (C -H, doublet, J 4.5 Hz), 4.96(C H, doublet, J 4.5 Hz.), 5.84 (CO CH CH quartet), 6.12 (CH CONH), 6.48and 6.88 (C ,CH AIS-quartet, J l 18 Hz), 7.1 to 7.7 (CH CH CO,ABCD-complex), and 8.75 (CO CH CH triplet) (Found: C, 49.7; H, 4.9; N,6.4; S, 14.6. C H N O S rH O required C, 49.9; H,

i 4.9; N, 6.45; S, 14.8%). Rf. 0.7 (System B and Rf0.34

(System C).

EXAMPLE 2 t-Butyl 3-(2-ethoxycarbonyl-2-triphenylphosphoranylideneethyl)-7B-formamidoceph- 3-em-4-carboxylate a.t-Butyl 3-bromomethyl-7l3-formamidoceph-3-em- 4-carboxylate A solutionof t-butyl 3-bromomethyl-7B- formamidoceph-3-em-4-carboxylate 1 B-oxide[3.95g

prepared as described in Preparation A4(a), (b) and (c) and ExampleB4(i) of Belgian Pat. No. 755,256] in dry methylene dichloride ml.) wascooled to -20 and phosphorus tribromide (1.43 ml.) in methylene di- 14chloride (9 ml.) added. After 17 minutes the mixture was treated with 5%aqueous sodium bicarbonate (until alkaline) and the organic layerseparated and washed with water and dried and evaporated in vacuo togive the title compound (3.45 g., 91%) as a cream-coloured foam [01],,+19.3 (c 0.9, CHCl k (EtOH) 270.6

nm (6, 5,280). u (CHBr 3420 (NH), 1790 (B-lactam), 1720 (C0 11) and 1700and 1505 (H.CONH), 1-

(CDCl 1.76 (CH0), 3.26 (NH, doublet, J 9 Hz), 4.17 (C -H, doubledoublet, J 9 and 4.5 Hz), 5.02 (C ,H, doublet, J 4.5 Hz), 5.61 (CH Br,singlet), 6.29 and 6.57 (C 3- CH AB-quartet, J 181-12) and 8.47 (C[CH b.b-Butyl 3-(2-Ethoxycarbonyl-2- triphenylphosphoranylideneethyl)-7B-formamidoce ph- 3-em-4-carboxylate A solution of t-butyl and3-bromomethyl-7B- formamidoceph-3-em-4-carboxylate (550 mg.) in ethylacetate (10 ml.) was treated with a solution of ethoxycarbonylmethylenetriphenylphosphorane (1.04 g., 2 equiv.) in ethylacetate (15.ml.) and the mixture stirred at 3 for 18 hours. The materialwhich had crystallised out after this time was isolated by filtrationand dissolved in methylene dichloride (ca 20 ml.). The organic solutionwas washed successively with 2 N- hydrochloric acid (3 X 10 ml), water.(3 X 10 ml.) and saturated sodium bicarbonate solution (7.5 ml.)containing an equal volume of water, and finally with water 10 ml. thendried, and evaporated in vacuo. The residue was crystallised from ethylacetate to give the title phosphorane-ester (220 mg.) as prisms.Theoriginal filtrate was evaporated in vacuo and the residue, inmethylene dichloride, was washed as described above. Crystallisation ofthe material obtained, after this treatment, from ethyl acetate gave afurther crop of the phosphorane-ester (57 mg.). The combined crops (277mg., 28%) were crystallised from acetone to give the pure title compound(170 mg.) as photosensitive white prisms, m.p. (darkening at ca 172) 186(vigorous decomp.), [01],, 117.8 (c 0.9, CHCl A (CHCI 266 (e 11,220),and 271 nm. (e 10,900), v,,,,,, (CHBr 3460 (NH), 1775 (B-lactam), 1710(CO R), 1700 and 1503 (CONH), 1600 (P=CCO Et), and 1442 (P-aryl) emf,7'(CDC13) 1.86 (HCO), ca. 2.6 (Ph), 3.06 (NH, doublet, J 9 Hz.), 4.38 (C-H, double doublet, J 4.5 and 9 Hz.), 5.28 (C H, doublet, J 4.5 Hz.), ca6.00 (COzCHzCHg), t0 (C(8)-CH2 and CH2C=P, complex), 8.64 (t-butyl) and8.84 and 9.55 (CO CH CH two triplets in ratio ca 1:2 [total 3 protons]corresponding to rotational isomers) (Found: C, 65.1; H, 5.85; N, 4.25;P, 4.45; S, C H N O PS requires C, 65.25; H, 5.8; N, 4.35; P, 4.8; S,4.95%).

The compound moves to the cathode on electrophoresis at pH 1.9.

EXAMPLE 3 ml.) and the mixture stirred at 27. for 22 hours,

in the dark. The mixture was cooled to ca 3 and stirred for 2 hoursafter which time precipitated material was.

collected by filtration and treated as described in Example lc to givethe ylid (3.85 g, 49%) as photosensitive white prisms (from ethylacetate), m.p. (darkening at ca 155) ca 178 (decomp), [M 61.5 (C 1.6,CHCl A (EtOH) 266 nm. (6 10,360) and 272 nm. (6 10,000); the infraredand p.m.r. spectra resembled those of material described above inExample 10.

EXAMPLE 4 t-Butyl 3-(2-Methoxycarbonyl-2-triphenylphosphoranylideneethyl )-7B-( 2-thienylacetamido)ceph-3-em-4-caboxy1ate.

A solution of t-butyl 3-iodomethyl-7B-(2- thienylacetamido)ceph-3-em-4-carboxylate 1.04 g, ca 2 mmole.) in ethyl acetate 10 ml.)was treated with a solution ofmethoxycarbonylmethylenetriphenylphosphorane (1.4 g., ca 4.2 mmole.) inwarm ethyl acetate (40 ml.) and the mixture stirred overnight at 3 inthe dark. Precipitated solid (1.23 g.) was isolated by filtration andwashed thoroughly with water. The insoluble material was dried in vacuoover phosphorus pentoxide, to give the title compound (584 mg., 40%) asfine needles, mp. ca 164 (decomp), [11] 63.6 (c 1.5, CHCI A inflex.(EtOH) 260 (6 10,170), 266 (6 10,330) and 273 nm. (a 9,880), v,, (CHBr3426 (NH), 1770 (B-lactam), 1710 (CO- R), 1680 and 1512 (CONH), 1604(P=C CO R) and 1440 (P-aryl) emf, 'r (CDC1 2.5 (Pb), 2.77 and 3.03(thienyl), 3.44 (NH, doublet, J 9 112.), 4.4 (C H, double doublet J 4.5and 9 Hz.), 5.25 (C ,H, ill-resolved doublet), 6.21 (CH CO), ca 6.44 (COCH ca 6.61 (CH C=P), ca 6.86 (C -CH2), and 8.64 (t-butyl) (Found; C,63.9; H, 5.4; N, 3.6; P, 4.0; S, 8.7. C H N O PS requires C, 64.45; H,5.4; N, 3.85; P, 4.25; S, 8.85%).

The initial ethyl acetate filtrate was evaporated in vacuo and theresidue in methylene dichloride, washed alternatively three times withN-hydrochloric acid (25 m1), and water (25 ml.). The organic phase wasthen washed with aqueous sodium bicarbonate, and water, and dried andevaporated in vacuo. The residue was crystallised from ethyl acetate togive an additional crop of the title compound (414 mg. 28.6%) (totalyield 998 mg., 68%) as needles, mp. ca 180 (decomp.), [M 63.35 (c 1.6,CHC1 inflex. (EtOl-l) 260 (6 10,330), 266 (e 10,470) and ca 271.5 nm. (510,030); the infrared and p.m.r. spectra of this material were similarto those of the first crop (Found: C, 64.7; H, 5.65; N, 3.6; P, 4.4; S,8.85%).

EXAMPLE 5 hydroeoisomers) 2.78 and 3.03 (thienyl), 3.42 and 3.10 (NH),two doublets), 4.22 and 4.28 (C 1-1, two double doublets, J 4.5 and 9112.), 5.08 (C ,H, doublet, J 4.5 and 9 Hz.), 5.08 (C ,H, doublet, J 4.5112.), 6.03 and 9.02 (CO CH CH quartet and triplet respectively, J 7Hz.), 6.17 (Cl-ECO), ca 5.6 to 7.0 (CH C=P) and (C ,CH and 8.59 and 8.6(t-butyl). The compound moves to the cathode on electropho resis at pH1.9.

1 claim: 1. A compound of the formula 5 Z l COOR ZP (R u 2 3 COORwherein R is thienylacetyl, phenylacetyl, fluorophenylacetyl,nitrophenylacety], aminophenylacetyl, acetoxyphenylacetyl,methoxyphenylacetyl, methylphenylacetyl, hydroxyphenylacetyl, orphenoxyacetyl; R is H or t-butyl; R is phenyl; R is lower alkyl orbenzyl and Z is S or S O; or an acid addition salt thereof.

2. A compound of the formula R NH $0011 N W), CH C=P (R COOR wherein Ris thienylacetyl, phenylacetyl, fluorophenylacetyl, nitrophenylacetyl,aminophenylacetyl. acetoxyphenylacety], methoxyphenylacetyl,methylphenylacetyl, hydroxyphenylacetyl or phenoxyacetyl; R is H ort-butyl', R is phenyl; R is lower alkyl or benzyl and Z is S or S O; oran acid addition salt thereof.

3. A compound of the formula E14 CONPLJZI/ S c0012 3 W; cti c=1= (a coca

1. A COMPOUND OF THE FORMULA
 2. A compound of the formula
 3. A compoundof the formula
 4. The compound of claim 3 which is t-butyl3-(2-ethoxycarbonyl-2-triphenylphosphoranylideneethyl)-7 Beta-(2-thienylacetamido)ceph-3-em-4-carboxylate.
 5. The compound of claim 3which is t-butyl3-(2-methoxycarbonyl-2-triphenylphosphoranylideneethyl)-7 Beta-(2-thienylacetamido)ceph-3-em-4-carboxylate.
 6. The compound of claim 3which is t-butyl3-(2-ethoxycarbonyl-2-triphenylphosphoranylideneethyl)-7 Beta-(2-thienylacetamido)ceph-3-em-4-carboxylate hydrochloride.